Radio frequency signal boosters for providing indoor coverage of high frequency cellular networks

ABSTRACT

Radio frequency signal boosters for high frequency cellular communications are provided herein. In certain embodiments, a signal booster system for providing high frequency wireless signal reception of a 5G network inside a building is provided. The signal booster system includes a primary unit configured to communicate with cellular infrastructure (e.g., a base station) of the 5G network through a window of a first room of the building, and an auxiliary unit for extending coverage from the first room to a second room. The auxiliary unit includes a housing located in the first room and having a base station antenna and booster circuitry integrated therewith. The auxiliary unit further includes a mobile station antenna in the second room and connected to the housing by a short cable.

REFERENCE TO RELATED CASES

This application is a continuation of U.S. patent application Ser. No.16/946,337, filed Jun. 17, 2020 and titled “RADIO FREQUENCY SIGNALBOOSTERS FOR PROVIDING INDOOR COVERAGE OF HIGH FREQUENCY CELLULARNETWORKS” which claims the benefit of priority under 35 U.S.C. § 119 ofU.S. Provisional Patent Application No. 62/864,044, filed Jun. 20, 2019and titled “RADIO FREQUENCY SIGNAL BOOSTERS FOR PROVIDING INDOORCOVERAGE OF HIGH FREQUENCY CELLULAR NETWORKS,” each of which is hereinincorporated by reference in its entirety.

FIELD

Embodiments of the invention relate to electronic systems and, inparticular, to radio frequency (RF) signal boosters.

BACKGROUND

A cellular or mobile network can include base stations for communicatingwith wireless devices located within the network's cells. For example,base stations can transmit signals to wireless devices via a downlink(DL) channel and can receive signals from the wireless devices via anuplink (UL) channel. In the case of a network operating using frequencydivision duplexing (FDD), the downlink and uplink communications areseparated in the frequency domain such that the frequency band operatesusing a pair of frequency channels. In the case of a network operatingusing time division duplexing (TDD), the downlink and uplinkcommunications are on a common frequency channel with uplink anddownlink transmissions occurring during different time slots.

A wireless device may be unable to communicate with any base stationswhen located in a portion of the mobile network having poor or weaksignal strength. To improve a network's signal strength and/or coverage,a radio frequency (RF) signal booster can be used to amplify signals inthe network. For example, the signal booster can be used to amplify orboost signals having frequencies associated with the frequency ranges ofthe network's uplink and downlink channels.

SUMMARY

The systems, methods, and devices of the invention each have severalaspects, no single one of which is solely responsible for its desirableattributes. Without limiting the scope of this invention as expressed bythe claims which follow, some features will now be discussed briefly.After considering this discussion, and particularly after reading thesection entitled “Detailed Description of Embodiments” one willunderstand how the features of this invention provide advantages thatinclude improved communications between base stations and mobile devicesin a wireless network.

In one aspect, a signal booster system for a high frequency cellularnetwork. The signal booster system includes a signal boosting unitincluding a base station antenna configured to receive a downlink signalof a frequency band and to transmit an amplified uplink signal of thefrequency band, wherein the base station antenna is directional. Thesignal boosting unit further includes booster circuitry configured toamplify an uplink signal of the frequency band to generate the amplifieduplink signal, and to amplify the downlink signal to generate anamplified downlink signal of the frequency band, wherein the frequencyband is higher than 20 gigahertz (GHz). The signal boosting unit furtherincludes a housing in which the base station antenna and the boostercircuitry are integrated therewith. The signal boosting unit furtherincludes a mobile station antenna configured to receive the uplinksignal and to transmit the amplified downlink signal, wherein the mobilestation antenna is configured to connect to the housing by a cable.

In another aspect, a signal boosting unit for a high frequency cellularnetwork. The signal boosting unit includes a base station antennaconfigured to receive a downlink signal and to transmit an amplifieduplink signal, wherein the base station antenna is directional. Thesignal boosting unit further includes booster circuitry configured toamplify an uplink signal to generate the amplified uplink signal, and toamplify the downlink signal to generate an amplified downlink signal, ahousing in which the base station antenna and the booster circuitry areintegrated therewith, and a mobile station antenna configured to receivethe uplink signal and to transmit the amplified downlink signal, whereinthe mobile station antenna is configured to connect to the housing by acable.

In another aspect, a signal boosting unit for a high frequency cellularnetwork is provided. The signal boosting unit includes a base stationantenna configured to receive a downlink signal and to transmit anamplified uplink signal, wherein the base station antenna isdirectional. The signal boosting unit further includes booster circuitryconfigured to amplify an uplink signal to generate the amplified uplinksignal, and to amplify the downlink signal to generate an amplifieddownlink signal, a mobile station antenna configured to receive theuplink signal and to transmit the amplified downlink signal, and ahousing in which the base station antenna, the booster circuitry, andthe mobile station antenna are integrated therewith.

In another aspect, a multi-unit signal booster system for a highfrequency cellular network is provided. The multi-unit signal boostersystem includes a primary signal boosting unit comprising a base stationantenna, booster circuitry, and a mobile station antenna. The multi-unitsignal booster system further includes an auxiliary signal boosting unitcomprising a base station antenna, booster circuitry, a housing in whichthe base station antenna and the booster circuitry are integratedtherewith, and a mobile station antenna configured to connect to thehousing by a cable. The base station antenna of the auxiliary signalboosting unit is configured to receive an amplified downlink signal fromthe mobile station antenna of the primary signal boosting unit, and themobile station antenna of the primary signal boosting unit is configuredto receive an amplified uplink signal from the base station antenna ofthe auxiliary signal boosting unit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of one embodiment of a signal boostersystem operating in a cellular network.

FIG. 2A is a schematic diagram of one embodiment of a signal boostingunit for a signal booster system.

FIG. 2B is a schematic diagram of another embodiment of a signalboosting unit for a signal booster system.

FIG. 2C is a schematic diagram of another embodiment of a signalboosting unit for a signal booster system.

FIG. 2D is a schematic diagram of another embodiment of a signalboosting unit for a signal booster system.

FIG. 2E is a schematic diagram of another embodiment of a signalboosting unit for a signal booster system.

FIG. 3 is a schematic diagram of another embodiment of a signal boostersystem operating in a cellular network.

FIG. 4A is a schematic diagram of another embodiment of a signalboosting unit for a signal booster system.

FIG. 4B is a schematic diagram of another embodiment of a signalboosting unit for a signal booster system.

FIG. 4C is a schematic diagram of another embodiment of a signalboosting unit for a signal booster system.

FIG. 4D is a schematic diagram of another embodiment of a signalboosting unit for a signal booster system.

FIG. 5 is a schematic diagram of another embodiment of a signal boostersystem operating in a cellular network.

FIG. 6 is a schematic diagram of one embodiment of booster circuitry fora signal boosting unit.

FIG. 7 is a schematic diagram of one embodiment of a signal boostingunit with selectable mobile station antennas for configurable radiationpattern.

FIG. 8A is a diagram of an overhead or frontal view of one embodiment ofa passive multiple-input multiple-output (MIMO) antenna array.

FIG. 8B is a diagram of a backside view of the passive MIMO antennaarray of FIG. 8A.

FIG. 9 is a schematic diagram of one embodiment of an active beamformingantenna array coupled to booster circuitry.

FIG. 10 is a schematic diagram of a signal boosting unit incommunication with a control device according to one embodiment.

DETAILED DESCRIPTION OF EMBODIMENTS

Various aspects of the novel systems, apparatus, and methods aredescribed more fully hereinafter with reference to the accompanyingdrawings. This disclosure may, however, be embodied in many differentforms and should not be construed as limited to any specific structureor function presented throughout this disclosure. Rather, these aspectsare provided so that this disclosure will be thorough and complete, andwill fully convey the scope of the disclosure to those skilled in theart. Based on the teachings herein one skilled in the art shouldappreciate that the scope of the disclosure is intended to cover anyaspect of the novel systems, apparatus, and methods disclosed herein,whether implemented independently of, or combined with, any other aspectof the invention. For example, an apparatus can be implemented or amethod can be practiced using any number of the aspects set forthherein. In addition, the scope of the invention is intended to coversuch an apparatus or method which is practiced using other structure,functionality, or structure and functionality in addition to or otherthan the various aspects of the invention set forth herein. It should beunderstood that any aspect disclosed herein can be embodied by one ormore elements of a claim.

Although particular aspects are described herein, many variations andpermutations of these aspects fall within the scope of the disclosure.Although some benefits and advantages of the preferred aspects arementioned, the scope of the disclosure is not intended to be limited toparticular benefits, uses, or objectives. Rather, aspects of thedisclosure are intended to be broadly applicable to different wirelesstechnologies, system configurations, networks, and transmissionprotocols, some of which are illustrated by way of example in thefigures and in the following description of the preferred aspects. Thedetailed description and drawings are merely illustrative of thedisclosure rather than limiting, the scope of the disclosure beingdefined by the appended claims and equivalents thereof.

Installing a signal booster system in a building can advantageouslyimprove both downlink signal strength and uplink signal strength ofmobile devices within the building. For example, walls of buildings canhave a shielding effect on signals transmitted and received by mobiledevices indoors. Furthermore, buildings can include metal, such asbeams, pipes, brackets, nails, and screws that operate to inhibitpropagation of radio waves.

The shielding effect of buildings can attenuate downlink signals fromthe base station within the buildings and/or attenuate uplink signalstransmitted from within the buildings. Under most conditions, theshielding effect can cause signal strength to drop. In one example, theshielding effect reduces signal strength below a threshold for cellularcommunication, thereby preventing successful voice and/or datacommunication. In another example, a mobile device operates with highertransmit power to compensate for a loss in signal strength fromshielding, and thus operates with greater power consumption and reducedbattery life. In yet another example, the mobile device operates withlower signal quality, and thus lower data rate and/or lower voicequality.

The amount of signal attenuation provided by buildings increases withsignal frequency. Thus, the impact of the shielding effect of buildingsis exacerbated in high frequency cellular communications, such ascellular networks communicating using millimeter wave (mmW) signals. Forinstance, signals communicated using Frequency Range 2 (FR2) of fifthgeneration (5G) technologies can suffer from very high loss whenpropagating through walls, windows, and/or other building structures.Loss is particularly significant for FR2 frequencies of about 20 GHz andhigher.

To provide indoor cellular signal coverage, a base station antenna of asignal booster system can be placed on a roof of a building to achieve arobust communication link with a base station, such as line-of-sightcommunication. Additionally, a mobile station antenna of the signalbooster system can be placed inside of the building, and used tocommunicate with mobile devices therein.

However, in such an implementation, the cost of installation can berelatively high. For example, such installation can necessitate atechnician, which can be costly and/or inconvenient. Furthermore, alength of a cable to reach the mobile station antenna can be severalmeters long, resulting in significant cable loss. Such cable loss canreduce transmit power and/or degrade receiver sensitivity. Moreover,cable loss is frequency dependent, and can be particularly exacerbatedwhen the cable carries RF signals over 6 GHz, such as millimeter wavesignals in the frequency range of 30 GHz to 300 GHz.

RF signal boosters for high frequency cellular communications areprovided herein. In certain embodiments, a signal booster system forproviding high frequency wireless signal reception of a 5G networkinside a building is provided. The signal booster system includes aprimary unit configured to communicate with cellular infrastructure(e.g., a base station) of the 5G network through a window of a firstroom of the building, and an auxiliary unit for extending coverage fromthe first room to a second room. The auxiliary unit includes a housinglocated in the first room and having a base station antenna and boostercircuitry integrated therewith. The auxiliary unit further includes amobile station antenna in the second room and connected to the housingby a short cable. One or more additional auxiliary units can be daisychained with the auxiliary unit to extend coverage into other rooms ofthe building.

FIG. 1 is a schematic diagram of one embodiment of a signal boostersystem 1 operating in a cellular network 20. The cellular network 20represents a portion of a 5G network.

As shown in FIG. 1 , the signal booster system 1 includes a signalboosting unit 4 that is installed in an interior of a building 10.Additionally, the building 10 includes an outer wall 11 having a window12 therein. The signal boosting unit 4 is attached to an interiorsurface of the window 12, in this example.

The signal boosting unit 4 includes a base station antenna, signalbooster circuitry, and a mobile station antenna integrated in a commonhousing. The signal boosting unit 4 can be attached to the window 12 ina wide variety of ways, such as by using a wide variety of mounts,adhesives, and/or fasteners.

Although FIG. 1 illustrates an example in which the signal boosting unit4 is attached to an interior of the window 12, the teachings herein areapplicable to other configurations of installation.

In certain implementations, the base station antenna of the signalboosting unit 4 is a directional antenna that is pointed in a directionof high signal strength in the wireless network 10. For instance, in theillustrated embodiment, the signal boosting unit 4 is configured towirelessly communicate with cellular infrastructure equipment 2, whichcan be, for example, a base station, a cellular repeater, or aninfrastructure signal booster. In one example, the cellularinfrastructure equipment 2 corresponds to a base station servicingmultiple homes in a neighborhood. In a second example, the cellularinfrastructure equipment 2 corresponds to an infrastructure signalbooster serving as an intermediary between a base station and the signalboosting unit 4.

In one embodiment, the signal boosting unit 4 and the cellularinfrastructure equipment 2 are separated by a distance of less thanabout 100 feet. Additionally, the cellular infrastructure equipment 2and the signal boosting unit 4 communicate with one another usingdirectional antennas to aid high frequency wireless transmissions fromthe cellular infrastructure equipment 2 to penetrate the window 12 andreach the signal boosting unit 4, and for high frequency wirelesstransmissions from the signal boosting unit 4 to penetrate the window 12and reach the cellular infrastructure equipment 2.

In certain implementations, the receive signal strength at the basestation antenna of the signal boosting unit 4 is in the range of about−50 dBm to about −70 dBm.

By communicating through the window 12, a wireless link between thesignal boosting unit 4 and the cellular infrastructure equipment 2 canbe achieved.

For example, at high frequencies, such as upper centimeter wavefrequencies in the range of 20 GHz to 30 GHz and millimeter wavefrequencies in the range of 30 GHz to 300 GHz, loss through the wall 11can be about 100 dB or more, thereby rendering wireless communicationsthrough the wall 11 infeasible. In contrast, the window 12 can have aloss of about 5 dB or more, for instance, about 5 dB for a transparentglass window, about 20 dB for a low emissivity (low-E) glass window, andabout 40 dB for a tinted glass window.

By using directional antennas, signal energy is focused to aid inovercoming loss of the window 12.

In certain implementations, the base station antenna of the signalboosting unit 4 has a directionality of at least 17 dBi. For example,communications of the signal boosting unit 4 can be directional with 36dBm or more of effective isotropic radiated power (EIRP).

The signal boosting unit 4 further includes an integrated mobile stationantenna for primarily radiating within an interior of the building 10.Thus, the mobile station antenna of the signal boosting unit 4 cancommunicate with mobile devices within the building 10, such as mobiledevices 3 a-3 c.

In certain implementations, the mobile station antenna of the signalboosting unit 4 has a directionality of 6 dBi or less. For example, themobile station antenna can be implemented as a 180° sector antenna thatradiates over a hemisphere, for instance with a base of the hemispheresubstantially aligned with the wall 11 and/or window 12. In anotherembodiment, the mobile station antenna of the signal boosting unit 4 isomnidirectional such that the mobile station antenna radiates over asphere.

Although the mobile network 20 is illustrated with specific examples ofnetwork equipment and user equipment, the mobile network 20 canimplemented with other types equipment. For instance, mobile devices caninclude mobile phones, tablets, laptops, wearable electronics (forinstance, smart watches), and/or other types of user equipment (UE)suitable for use in a wireless communication network. Furthermore,network equipment can include base stations, signal repeaters,infrastructure boosters, and/or other cellular infrastructure. Moreoverany number of such devices and equipment can be present in the network20.

The signal boosting unit 4 can be implemented using any suitablecombination of features disclosed herein. Although an example with ahome is shown, a signal booster system can be installed in a variety oftypes of buildings, such as homes, offices, commercial premises,factories, garages, barns, and/or any other suitable building.

In certain implementations, the mobile devices 3 a-3 c can communicateat least in part over multiple frequency bands, including one or morecellular bands associated with 3GPP 5G communications. Such 5Gcommunications can include FR2 communications, such as those of 20 GHzor higher. Signals used in 5G communications are also referred to hereinas 5G new radio (5G NR) signals.

In certain implementations, the signal boosting unit 4 can be configuredto boost signals associated with two or more frequency bands so as toimprove network reception for each of the mobile devices 3 a-3 c.Configuring the signal boosting unit 4 to service multiple frequencybands can improve network signal strength. For example, the signalboosting unit 4 can improve network signal strength of devices using thesame or different frequency bands, the same or different wirelesscarriers, and/or the same or different wireless technologies.Configuring the signal boosting unit 4 as a multi-band booster can avoidthe cost of separate signal boosters for each specific frequency bandand/or wireless carrier.

FIG. 2A is a schematic diagram of one embodiment of a signal boostingunit 50 for a signal booster system. The signal boosting unit 50includes a housing 40, a base station antenna 41, a mobile stationantenna 42, and booster circuitry 43.

The signal boosting unit 50 of FIG. 2A illustrates one embodiment of thesignal boosting unit 4 of FIG. 1 .

The base station antenna 41, the mobile station antenna 42, and thebooster circuitry 43 are integrated on and/or within the housing 40 ofthe signal boosting unit 50. The base station antenna 41 receives adownlink signal, which is amplified by the booster circuitry 43 togenerate an amplified downlink signal that is transmitted on the mobilestation antenna 42. Additionally, the mobile station antenna 42 receivesan uplink signal, which is amplified by the booster circuitry 43 togenerate an amplified uplink signal that is transmitted on the basestation antenna 41. In certain implementations, the signal boosting unit50 operates at least in part using time division duplexing (TDD) inwhich uplink and downlink transmissions occur in different time slots orwindows.

The booster circuitry 43 provides amplification to RF signals associatedwith one or more uplink and downlink channels. The booster circuitry 43can include a wide variety of circuitry and/or components. Examples ofcircuitry and components of the booster circuitry 43 include, but arenot limited to, amplifiers (for instance, LNAs, power amplifiers (PAs),variable gain amplifiers (VGAs), programmable gain amplifiers (PGAs),and/or other amplification circuits), filters (for instance, surfaceacoustic wave (SAW) filters, bulk acoustic wave (BAW) filters, film bulkacoustic resonator (FBAR) filters, active circuit filters, passivecircuit filters, and/or other filtering structures), duplexers,circulators, frequency multiplexers (for instance, diplexers,triplexers, or other multiplexing structures), switches, impedancematching circuitry, attenuators (for instance, digital-controlledattenuators such as digital step attenuators (DSAs) and/oranalog-controlled attenuators such as voltage variable attenuators(VVAs)), detectors, monitors, couplers, and/or control circuitry.

FIG. 2B is a schematic diagram of another embodiment of a signalboosting unit 60 for a signal booster system.

The signal boosting unit 60 of FIG. 2B is similar to the signal boostingunit 50 of FIG. 2A, except that the signal boosting unit 60 furtherincludes a pluggable mobile station antenna 51 having a pluggable cable53. As shown in FIG. 2B, an outer surface of the housing 40 isimplemented with a port 52 that receives the pluggable cable 53, therebyallowing the pluggable mobile station antenna 51 to be selectivelyconnected to the housing 40. Although depicted as being pluggable on oneend, either or both ends of the cable 53 can implemented to bepluggable.

With continuing reference to FIG. 2B, the signal boosting unit 60further includes a switch 55, and an antenna detector 56 for controllingthe switch 55 based on whether or not the pluggable mobile stationantenna 51 is detected. For example, the antenna detector 56 can connectthe pluggable mobile station antenna 51 to the booster circuitry 43 whenthe pluggable mobile station antenna 51 is detected, and connect themobile station antenna 42 to the booster circuitry 43 when the pluggablemobile station antenna 51 is not detected.

FIG. 2C is a schematic diagram of another embodiment of a signalboosting unit 70 for a signal booster system.

The signal boosting unit 70 of FIG. 2C is similar to the signal boostingunit 50 of FIG. 2A, except that the signal boosting unit 70 of FIG. 2Cincludes a specific implementation of antennas. In particular, thesignal boosting unit 70 includes a passive multiple-inputmultiple-output (MIMO) base station antenna array 61 and a sector mobilestation antenna 62.

The passive MIMO base station antenna array 61 includes multiple antennaelements having spatial diversity, and is also referred to herein as apassive spatial diversity antenna array. In certain implementations, thepassive MIMO base station antenna array 61 includes an array of planarantennas, such as patch antennas, arranged on a substrate, such as aprinted circuit board (PCB). By implementing a base station antenna as apassive MIMO base station antenna array, enhanced directivity and/orhigher signal-to-noise ratio (SNR) can be achieved.

With continuing reference to FIG. 2C, implementing the signal boostingunit 70 with the sector mobile station antenna 62 aids in communicatingwith mobile phones or other UE positioned throughout a room. In certainimplementations, the sector mobile station antenna 62 can be implementedwith a radiation pattern that substantially covers a hemisphere, forinstance, at least 75 percent of the hemisphere.

Thus, in certain implementations the sector mobile station antenna 62provides about 180° of angular coverage with respect to the polar angleand azimuthal angle in a spherical coordinate system. When covering atleast 75 percent of the hemisphere, the sector mobile station antenna 62provides between about 135° and about 180° of angular coverage withrespect to the polar angle and azimuthal angle.

FIG. 2D is a schematic diagram of another embodiment of a signalboosting unit 80 for a signal booster system.

The signal boosting unit 80 of FIG. 2D is similar to the signal boostingunit 70 of FIG. 2C, except that the signal boosting unit 80 of FIG. 2Dincludes a base station antenna implemented as an active beamformingbase station antenna array 71 rather than as the passive MIMO basestation antenna array 61 as in FIG. 2C.

Implementing the signal boosting unit 80 with the active beamformingbase station antenna array 71 aids in providing beamforming that canallow the signal boosting unit 80 to control the angle of signalstransmitted or received. For example, the active beamforming basestation antenna array 71 can include an array of antenna elements eachassociated with a controllable gain element and a controllable phaseelement. By controlling the gain and phase of signals transmitted and/orreceived by each element of the array, beamforming can be achieved.

For instance, with respect to signal transmission, the gain and phase ofthe signals transmitted on each antenna element can be controlled suchthat the signals radiated from the antenna elements combine usingconstructive and destructive interference to generate an aggregatetransmit beam pointing in a desired direction. Additionally, withrespect to the signal reception, the gain and phase of signals receivedon each antenna element can be controlled such that the combinedreceived signal favors signals received from a particular direction.

Implementing the signal boosting unit 80 with the active beamformingbase station antenna array 71 provides a number of advantages. Forexample, when the signal boosting unit 80 is installed in the building10 of FIG. 1 , beamforming can be used to compensate for an installationerror in pointing the signal boosting unit toward the cellularinfrastructure equipment 2.

Moreover, in certain implementations, the signal boosting unit 80 can beimplemented to regularly realign or calibrate a direction ofbeamforming, thereby compensating for changes in the relative positionsand/or orientations of the signal boosting unit 80 and/or the cellularinfrastructure equipment 2 over time. For instance, when installed onthe window 12, the position of the signal boosting unit 80 can changewhen the window 12 is opened or closed and/or by occupants (includingpeople and/or pets) of the building 10. Furthermore, the cellularinfrastructure equipment 2 can also move over time, for instance, due toweather and/or handling.

Accordingly, beamforming can be used to align communications between thesignal boosting unit 80 and the cellular infrastructure equipment 2,thereby enhancing the strength of the wireless communication linktherebetween.

FIG. 2E is a schematic diagram of another embodiment of a signalboosting unit 90 for a signal booster system.

The signal boosting unit 90 of FIG. 2E is similar to the signal boostingunit 50 of FIG. 2A, except that the signal boosting unit 90 of FIG. 2Eincludes a specific implementation of a base station antenna. Inparticular, the signal boosting unit 90 includes a parabolic antenna 81for serving as a base station antenna.

FIG. 3 is a schematic diagram of another embodiment of a signal boostersystem 140 operating in a cellular network 120.

The signal booster system 140 includes a signal boosting unit 141including a housing 144 in which a base station antenna 147 and boostercircuitry 148 have been integrated. Additionally, the signal boostingunit 141 further includes a mobile station antenna 145 connected to thehousing 144 by way of a cable 146.

Accordingly, in comparison to the signal boosting unit 4 of FIG. 1 inwhich booster circuitry, the mobile station antenna, and the basestation antenna are all integrated in a common housing, the signalboosting unit 141 separates the housing 144 (in which booster circuitry147 and a base station antenna 148 are integrated) from the mobilestation antenna 145 by the cable 146.

Separating the mobile station antenna 145 in this manner can enhanceantenna-to-antenna isolation between mobile station and base stationantennas, thereby inhibiting unintended oscillations from occurring.

In certain implementations, the length of the cable 146 is less thanabout 5 feet. Implementing the cable 146 with short length can aid inreducing cable loss, thereby enhancing the strength of indoor signalcoverage. For example, at upper centimeter wave frequencies, cable losscan in the range of about 0.5 dB to 1 dB per foot of cable.

In certain implementations, the cable 146 is pluggable on either or bothends.

FIG. 4A is a schematic diagram of another embodiment of a signalboosting unit 210 for a signal booster system. The signal boosting unit210 of FIG. 4A illustrates one embodiment of the signal boosting unit141 of FIG. 3 .

The signal boosting unit 210 includes a housing 200 including boostercircuitry 43 therein. The base station antenna 41 and the boostercircuitry 43 are integrated in this example. For example, the basestation antenna 41 can be implemented within and/or on the housing 200.The signal boosting unit 210 further includes a mobile station antenna43 connected to the booster circuitry 200 by a cable 201, which in someimplementations is pluggable on one or both ends. In certainimplementations, the cable is less than 5 feet.

FIG. 4B is a schematic diagram of another embodiment of a signalboosting unit 220 for a signal booster system.

The signal boosting unit 220 of FIG. 4B is similar to the signalboosting unit 210 of FIG. 4A, except that the signal boosting unit 220of FIG. 4B includes a specific implementation of antennas. Inparticular, the signal boosting unit 210 includes a passive MIMO basestation antenna array 61 and a sector mobile station antenna 62, whichcovers about 180° of angular range in some implementations.

FIG. 4C is a schematic diagram of another embodiment of a signalboosting unit 230 for a signal booster system.

The signal boosting unit 230 of FIG. 4C is similar to the signalboosting unit 210 of FIG. 4A, except that the signal boosting unit 230of FIG. 4C includes a specific implementation of antennas. Inparticular, the signal boosting unit 230 includes an active beamformingbase station antenna array 71 and a sector mobile station antenna 62,which covers about 180° of angular range in some implementations.

FIG. 4D is a schematic diagram of another embodiment of a signalboosting unit 240 for a signal booster system.

The signal boosting unit 240 of FIG. 4D is similar to the signalboosting unit 210 of FIG. 4A, except that the signal boosting unit 240of FIG. 4D includes a parabolic antenna 81 for serving as the basestation antenna.

FIG. 5 is a schematic diagram of another embodiment of a signal boostersystem 331 operating in a cellular network 350. The cellular network 350represents a portion of a 5G network.

As shown in FIG. 5 , the signal booster system 331 is installed in abuilding 320, which includes a first room 327 a, a second room 327 b,and a third room 327 c. Additionally, the building 320 includes an outerwall 321 having a window 322 therein. The signal booster system 331includes a primary signal boosting unit 4 installed in the first room327 a of the building 320. The signal booster system 331 furtherincludes a first secondary or auxiliary signal boosting unit 340 ainstalled in the first and second rooms of the building 320, and asecond auxiliary signal boosting unit 340 b installed in the second andthird rooms of the building 320.

The primary signal boosting unit 4 is attached to an interior surface ofthe window 322, in this example. Although FIG. 5 illustrates an examplein which the primary signal boosting unit 4 is attached to an interiorof the window 322, the teachings herein are applicable to otherconfigurations of installation.

Furthermore, although the first auxiliary signal boosting unit 340 a andthe second auxiliary signal boosting unit 340 b are illustrated as beingplaced on a floor of a room, other configurations are possible, such asimplementations in which the auxiliary signal boosting unit is mountedon a wall or ceiling.

As shown in FIG. 5 , the first room 327 a and the second room 327 b areseparated by a first interior wall 323. Although the primary signalboosting unit 4 provides cellular signal reception in the first room 327a (for instance, to the mobile device 3 a), the first interior wall 323prevents the primary signal boosting unit 4 from directly transmittinghigh frequency signals to or receiving high frequency signals frommobile devices in the second room 327 b (for instance, the mobile device3 b). Additionally, the second room 327 b and the third room 327 c areseparated by a second interior wall 324 having a door 325. Although theprimary signal boosting unit 4 provides cellular signal reception in thefirst room 327 a, the first interior wall 323 and the second interiorwall 324 prevents the primary signal boosting unit 4 from directlytransmitting high frequency signals to or receiving high frequencysignals from mobile devices in the third room 327 c (for instance, themobile device 3 c).

To extend coverage to the second room 327 b of the building 320, thefirst auxiliary signal boosting unit 340 a has been included. The firstauxiliary signal boosting unit 340 a includes a housing 344 a in which abase station antenna 347 a and booster circuitry 348 a have beenintegrated. The first auxiliary signal boosting unit 340 a furtherincludes a mobile station antenna 345 a connected to the housing 344 aby way of a cable 346 a. The cable 346 a is provided through theinterior wall 323 and carries signals between the booster circuitry inthe housing 344 a located in the first room 327 a and the mobile stationantenna 345 a located in the second room 327 b.

Including the first auxiliary signal boosting unit 340 a allows mobiledevices in the second room 327 b (for instance, the mobile device 3 b)to communicate with the cellular infrastructure equipment 2.

For example, when the mobile device 3 b is transmitting, the mobilestation antenna 345 a in the second room 327 b provides the receiveduplink signal from the mobile device 3 b to the housing 344 a in thefirst room 327 a. Additionally, booster circuitry 348 a in the housing344 a amplifies the uplink signal to generate an amplified uplinksignal, which is transmitted by the base station antenna 347 aintegrated with the housing 344 a of the first auxiliary signal boostingunit 340 a. The primary signal boosting unit 4 receives the uplinksignal from the first auxiliary signal boosting unit 340 a, andtransmits an amplified uplink signal to the cellular infrastructureequipment 2.

With respect to downlink, the primary signal boosting unit 4 receives adownlink signal from the cellular infrastructure equipment 2, andtransmits an amplified downlink signal to the first auxiliary signalboosting unit 340 a. The first auxiliary signal boosting unit 340 areceives the downlink signal using the base station antenna 347 a in thefirst room 327 a, and transmits an amplified downlink signal to themobile device 3 b using the mobile station antenna 345 a in the secondroom 327 b.

To further extend coverage to the third room 327 c of the building 320,the second auxiliary signal boosting unit 340 b has been included. Thesecond auxiliary signal boosting unit 340 b includes a housing 344 b inwhich a base station antenna 347 b and booster circuitry 348 b have beenintegrated. The second auxiliary signal boosting unit 340 b furtherincludes a mobile station antenna 345 b connected to the housing 344 bby way of a cable 346 b. The cable 346 b is provided under a door 325 ofthe interior wall 324, and carries signals between the booster circuitryin the housing 344 b located in the second room 327 b and the mobilestation antenna 345 b located in the third room 327 c.

Accordingly, the primary signal boosting unit 4, the first auxiliarysignal boosting unit 340 a, and the second auxiliary signal boostingunit 340 b are arranged in a communication chain, also referred toherein as a daisy chain.

Although an example with two auxiliary signal boosting units isdepicted, more or fewer auxiliary signal boosting units can be included.Furthermore, although an example in which a single communication chainis depicted, a signal booster system can include multiple communicationchains. For instance, the primary signal boosting unit 4 can communicatenot only with the first auxiliary signal boosting unit 340 a, but alsowith one or more other auxiliary signal boosting units associated withdifferent communication chains. Such communication chains can spanmultiple rooms of a structure, including not only laterally acrosswalls, but also configurations across floors. For instance, multiplecommunication chains can be used to provide indoor cellular highfrequency signal coverage (for instance, millimeter wave 5G swerve)within a multi-story building.

The number of signal boosting units (including a primary signal boostingunit and any auxiliary signal boosting units) can be selected based onlink budget and noise. For instance, the link budget can correspond toan accounting of signal gains and losses between a base station (forinstance, cellular infrastructure equipment 2) and UE (for instance,mobile device 3 c) through all units along the communication chain.

An auxiliary signal boosting unit can be implemented in a wide varietyof ways, including, but not limited to, using any of the embodiments ofsignal boosting units depicted in FIGS. 4A-4D.

Although depicted using a primary signal boosting unit 4 in which thebase station antenna, the mobile station antenna, and the boostercircuitry are integrated in a common housing, other implementations arepossible. For example, the primary signal boosting unit 4 can be omittedin favor of using the signal boosting unit 141 of FIG. 3 .

In certain implementations, each of the auxiliary signal boosting unitsincludes a directional base station antenna. For example, the basestation antenna of the first auxiliary signal boosting unit 340 a andthe base station antenna of the second auxiliary signal boosting unit340 b can each be implemented with a directionality of at least 17 dBi.

By using directional antennas, the base station antenna of the firstauxiliary signal boosting unit 340 a can generate a robust communicationlink with the mobile station antenna of the primary signal boosting unit4, and the base station antenna of the second auxiliary signal boostingunit 340 b can generate a robust communication link with the mobilestation antenna 345 a of the first auxiliary signal boosting unit 340 a.

In a first example, the base station antenna of the first auxiliarysignal boosting unit 340 a and/or the base station antenna of the secondauxiliary signal boosting unit 340 b is implemented as a passive MIMObase station antenna array, thereby realizing high antenna gain in adesired direction using an array of antenna elements with spatialdiversity.

In a second example, the base station antenna of the first auxiliarysignal boosting unit 340 a and/or the base station antenna of the secondauxiliary signal boosting unit 340 b is implemented as an activebeamforming base station antenna array.

In such an implementation, the base station antenna of an auxiliarysignal boosting unit can adjust or change the angle of beams transmittedor received on the base station antenna to enhance performance. Forexample, beamforming can be used to compensate for an installation errorin pointing the base station antenna of the auxiliary signal boostingunit toward a mobile station antenna of another signal boosting unit.

Moreover, in certain implementations, the auxiliary signal boosting unitcan be implemented to regularly realign or calibrate a direction ofbeamforming, thereby compensating for changes in the relative positionsand/or orientations between the auxiliary signal boosting unit andanother signal boosting unit over time. For instance, the beamformingcalibration can be used to provide adjustment when one or more of thesignal boosting units are moved (for instance, accidentally bumped) bypeople and/or pets in the building 320.

Accordingly, beamforming can be used to align communications between apair of signal boosting units, thereby enhancing the strength of thewireless communication link therebetween.

In certain implementations, the mobile station antenna of an auxiliarysignal boosting unit has a directionality of less than 6 dBi or less,thereby allowing the mobile station antenna to transmit and receivesignals over a wide angular range. For example, the mobile stationantenna of an auxiliary signal booster can be implemented to radiationpattern substantially covering a hemisphere, for instance, at least 75percent of the hemisphere. In another embodiment, the mobile stationantenna of an auxiliary signal boosting unit is omnidirectional.

FIG. 6 is a schematic diagram of one embodiment of booster circuitry 460for a signal boosting unit. The booster circuitry 460 includes adownlink amplification circuit 421, an uplink amplification circuit 422,a first TDD switch 423, a second TDD switch 424, a directional coupler425, a downconverting mixer 426, a TDD synchronization detection circuit427, a remote monitoring circuit 428, and a controller 429. The boostercircuitry 460 further includes a base station antenna terminal BS forconnecting to a base station antenna, and a mobile station antennaterminal MS for connecting to a mobile station antenna.

Although one embodiment of booster circuitry for a primary or auxiliaryboosting unit is shown, the teachings herein are applicable to boostercircuitry implemented in a wide variety of ways.

As shown in FIG. 6 , the first TDD switch 423 selectively connects thebase station antenna terminal BS to an input of the downlinkamplification circuit 421 or to an output of the uplink amplificationcircuit 422. Additionally, the second TDD switch 424 selectivelyconnects the mobile station antenna terminal MS to an output of thedownlink amplification circuit 421 or to an input of the uplinkamplification circuit 422.

Thus, a state of the first TDD switch 423 and the second TDD switch 424can be controlled to selectively provide amplification to a downlinksignal DL received on the base station antenna terminal BS or to anuplink signal UL received on the mobile station antenna terminal MS.

For example, when the first TDD switch 423 and the second TDD switch 424select the downlink amplification circuit 421, the downlinkamplification circuit 421 amplifies the downlink signal DL received onthe base station antenna terminal BS to generate an amplified downlinksignal ADL on the mobile station antenna terminal MS. Additionally, whenthe first TDD switch 423 and the second TDD switch 424 select the uplinkamplification circuit 422, the uplink amplification circuit 422amplifies the uplink signal UL received on the mobile station antennaterminal MS to generate an amplified uplink signal AUL on the basestation antenna terminal BS.

In the illustrated embodiment, the booster circuitry 460 includes theTDD synchronization detection circuit 427 for controlling the state ofthe first TDD switch 423 and the second TDD switch 424. As shown in FIG.6 , the TDD synchronization detection circuit 427 is coupled to the basestation antenna terminal BS by way of the directional coupler 425 andthe downconverting mixer 426. Although one location along the downlinksignal path is shown for coupling the TDD synchronization detectioncircuit 427, other implementations are possible. For example, in anotherembodiment, TDD synchronization detection is provided after amplifyingthe downlink signal. For instance, the TDD synchronization detectioncircuit 427 can be positioned at the output of the downlinkamplification circuit 421.

The directional coupler 425 serves to generate a sensed downlink signalbased on sensing the downlink signal DL received on the base stationantenna terminal BS. Additionally, the downconverting mixer 426 servesto downconvert the sensed downlink signal to generate a downconverteddownlink signal for processing by the TDD synchronization detectioncircuit 427. Although not shown in FIG. 6 , the downconverting mixer 426receives a local oscillator (LO) signal for controlling the frequencyused for downconversion. In certain implementations, the frequency ofthe LO signal can be selected to be about equal to the carrier frequencyof the downlink signal DL, for instance, about 28 GHz, in this example.In other implementations, an intermediate frequency (IF) is used fordownconversion.

With continuing reference to FIG. 6 , the TDD synchronization detectioncircuit 427 processes the downconverted downlink signal to recovernetwork timing information indicating time slots used for uplink anddownlink transmissions. Accordingly, the TDD synchronization detectioncircuit 427 processes the downconverted downlink signal to determinenetwork timing information, and uses the recovered network timinginformation to control the state of the first TDD switch 423 and thesecond TDD switch 424.

Although shown as including a first TDD switch 423 and a second TDDswitch 424, other implementations are possible. For example, in anotherembodiment a circulator is used in place of or combined with a TDDswitch to allow handling of higher signal power.

In the illustrated embodiment, the booster circuitry 460 includes theTDD synchronization detection circuit 427. The TDD synchronizationdetection circuit 427 processes the downconverted downlink signal torecover network timing information, the TDD synchronization detectioncircuit 427 need not fully recover data carried by the downlink signalDL.

By including the TDD synchronization detection circuit 427, the downlinkamplification circuit 421 is activated during time slots used fortransmitting the downlink signal DL, and the uplink amplificationcircuit 422 is activated during time slots used for transmitting theuplink signal UL.

In the illustrated embodiment, the downlink amplification circuit 421includes a low noise amplifier (LNA) 441, a first bandpass filter 442, acontrollable gain amplifier 443, a second bandpass filter 444, and apower amplifier (PA) 445. Additionally, the uplink amplification circuit422 includes an LNA 451, a first bandpass filter 452, a controllablegain amplifier 453, a second bandpass filter 454, and a PA 455. In thisexample, the downlink amplification circuit 421 and the uplinkamplification circuit 422 are implemented for providing boosting ofuplink and downlink signals, respectively, in the 28 GHz band. However,the teachings herein are applicable to other frequency ranges and bands.

Although one embodiment of downlink and uplink amplification circuits isshown, the teachings herein are applicable to downlink and uplinkamplification circuits implemented in a wide variety of ways.

As shown in FIG. 6 , neither the downlink amplification circuit 421 northe uplink amplification circuit 422 include any mixers for shifting thefrequency of the signals. In certain implementations herein, a signalbooster unit operates with wideband operation amplifying multiplechannels of (for instance, a full bandwidth of) a 5G NR band (such asn261, n257, n258, or n260) and/or amplifies FR2/millimeter wave signalswithout any frequency upconversion or frequency downconversion.

The controller 429 provides a number of control functionalitiesassociated with the booster circuitry 460. The controller 429 can beimplemented in a wide variety of ways, for instance, as amicroprocessor, microcontroller, computer processing unit (CPU), and/orother suitable control circuitry. Example functions of the controller429 are power control (for instance, automatic gain control),oscillation detection, and/or shutdown.

In the illustrated embodiment, the controller 429 provides control overgain of the controllable gain amplifier 443 of the downlinkamplification circuit 421 and the controllable gain amplifier 453 of theuplink amplification circuit 422. However, other implementation of gaincontrol are possible. For example, the control circuitry can control theattenuation provided by controllable attenuation components (forinstance, digital step attenuators and/or voltage variable attenuators)and/or the gain provided by controllable gain amplifiers (for instance,variable gain amplifiers and/or programmable gain amplifiers).

Although not depicted in FIG. 6 , the downlink amplification circuit 421and/or the uplink amplification circuit 422 can include one or morepower detectors for generating power detection signals for thecontroller 429. Additionally or alternatively, other detectors orsensors, such as a temperature detector, can aid the controller 429 inproviding information used for control functionality.

Although depicted as including one uplink amplification circuit and onedownlink amplification circuit, multiple uplink amplification circuitsand downlink amplification circuits can be included, for instance, foreach frequency band for which the booster circuitry provides signalboosting.

In certain implementations, the controller 429 is shared by multipleuplink amplification circuits and/or downlink amplification circuits.For example, the controller 429 can correspond to a processing chip (forinstance, a microprocessor chip, microcontroller chip, or CPU chip) thatprovides centralized control of a signal boosting unit.

In the illustrated embodiment, the booster circuitry 460 furtherincludes the remote monitoring circuit 428, which provides remotemonitoring. In certain implementations, the remote monitoring circuit428 includes a transceiver for communicating information pertaining tooperation of a signal boosting unit with another device, such as acomputer (for instance, a desktop or laptop), a tablet, or a mobilephone. Thus, remote access and control to a signal booster system can beprovided. Remote monitoring and control is wireless in certainimplementations, for instance, by using a wireless interface controlledby a cellular modem and/or Internet of Things (IoT) modem.

Examples of such information includes, but is not limited to, whetherthe signal boosting unit is powered, whether boosting is active for oneor more bands, antenna status, a temperature condition, and/or whetheroscillation/pre-oscillation has occurred. In certain implementations,the remote monitor 428 can be used to receive instructions for remoteshut-down or power control, remote control of gain and/or attenuation(including, for example, band specific control), and/or remote controlof antenna selection (for instance, in multi-antenna configurations). Inyet another example, the remote monitor 428 receives settings forbeamforming (see, for example, the embodiment of FIG. 10 ).

In the illustrated embodiment, the booster circuitry 460 operateswithout frequency upconversion and without frequency downconversion.Thus, the frequency of an amplified uplink signal outputted by thebooster circuitry 460 is equal to the frequency of the received uplinksignal, and the frequency of the amplified downlink signal outputted bythe booster circuitry 460 is equal to the frequency of the receiveddownlink signal.

By operating without frequency upconversion/downconversion, lowerlatency group delay is provided. This in turns facilitates enhancedlayer performance and/or increased tolerance to multipath signals.

FIG. 7 is a schematic diagram of one embodiment of a signal boostingunit 510 with selectable mobile station antennas for configurableradiation pattern. The signal boosting unit 510 includes a housing 200having a base station antenna 41 and booster circuitry 43 integratedtherewith. The signal boosting unit 510 further includes a pluggablecable 501 and different mobile station antennas 503 a, 503 b, . . . 503n with different radiation patterns.

The signal boosting unit 510 is implemented to operate with a selectedmobile station antenna chosen from multiple mobile station antennashaving different radiation patterns suitable for different rooms of abuilding. For example, the pluggable cable 501 can be plugged into themobile station antenna 503 a, the mobile station antenna 503 b, or themobile station antenna 503 n, each of which have a different radiationpattern, for instance, different amounts of directionality. Although anexample with three mobile station antennas 503 a, 503 b, . . . 503 n isshown, more or fewer mobile station antennas can be available forconnection as indicated by the ellipses.

In certain implementations, the pluggable cable 501 is less than 5 feet.Although shown as being pluggable on one end, the pluggable cable 501can be pluggable on either or both ends.

In certain implementations, the housing 200, the pluggable cable 501,and the mobile station antennas 503 a, 503 b, . . . 503 n are includedin a kit. Additionally, the user selects one of the mobile stationantennas 503 a, 503 b, . . . 503 n from the kit having a radiationpattern suitable for a desired deployment of the signal boosting unit510. For instance, a mobile station antenna having a radiation patternsuitable for a particular shaped room can be selected. In otherimplementations, one or more of the mobile station antennas 503 a, 503b, . . . 503 n are sold separately (for instance, individually), and auser purchases or otherwise acquires one or more of the mobile stationantennas.

FIG. 8A is a diagram of an overhead view of one embodiment of a passiveMIMO antenna array 610. FIG. 8B is a diagram of a backside view of thepassive MIMO antenna array 610 of FIG. 8A. The passive MIMO antennaarray 610 includes a first patch antenna element 602 a, a second patchantenna element 602 b, a third patch antenna element 603 c, and a fourthpatch antenna element 602 d formed on a first or front surface of anantenna substrate 601, such as a printed circuit board (PCB).

The passive MIMO antenna array 610 illustrates one embodiment of apassive MIMO antenna array for serving as a base station antenna.However, the teachings herein are applicable to base station antennasimplemented in a wide variety of ways, including, but not limited to,using other configurations of passive MIMO antenna arrays or otherdirectional antennas.

The antenna elements 602 a-602 d are positioned in different physicallocations to provide spatial diversity. As shown in FIG. 6B, the antennaelements 602 a-602 d are controlled using a common signal feed 603.Thus, when the passive MIMO antenna array 610 is receiving, the signalsare combined to form an aggregate or combined receive signal.Additionally, when the passive MIMO antenna array 610 is transmitting, atransmit signal received at the common signal feed 603 is split suchthat the transmit signal is radiated using each of the antenna elements602 a-602 d.

Although shown with four antenna element in a 2×2 array, other numbersof antenna elements (for instance, larger arrays) and/or otherarrangements of antenna elements are possible.

FIG. 9 is a schematic diagram of one embodiment of an active beamformingantenna array 710 coupled to booster circuitry 43.

In the illustrated embodiment, the active beamforming antenna array 710includes first to eighth antenna elements 701 a-701 h, respectively,first to eighth gain/phase control circuits 702 a-702 h, respectively,and first to seventh combiners/splitters 704 a-704 g, respectively.

The active beamforming antenna array 710 illustrates one embodiment ofan active beamforming antenna array for serving as a base stationantenna. However, the teachings herein are applicable to base stationantennas implemented in a wide variety of ways, including, but notlimited to, using other configurations of active beamforming antennaarrays or other directional antennas.

Although shown as including an array of eight antenna elements, more orfewer antenna elements and corresponding signal processing circuitry canbe included.

With reference to FIG. 9 , beamforming of a transmit beam isaccomplished by separately controlling the phase and magnitude of an RFtransmit signal (for instance, an uplink signal for transmission) fromthe booster circuitry 43 using the gain/phase control circuits 702 a-702h, thereby focusing RF energy in a particular direction. Whenbeamforming a receive beam, the gain and phase of RF signals received bythe antenna elements 702 a-702 h are controlled such that the aggregatereceive signal (for instance, a downlink signal) provided to the boostercircuitry 43 indicates electromagnetic energy received by the antennaarray from a particular direction.

Accordingly, beamforming is applicable to both transmit and receivedirections. Additionally, the combiners/splitters 704 a-704 g providesignal splitting when the antenna array is transmitting, and providesignal combining when the antenna array is receiving.

In certain implementations, the gain/phase control circuits 702 a-702 hare formed on a semiconductor die that includes a serial interface, suchas an I²C bus, that receives data for selecting a particular beampattern (for instance, a transmit or receive beam of a particular angleand strength) for beamforming.

Such settings for beamforming can be controlled in a wide variety ofways. In certain implementations, a controller of the booster circuitry43 (for instance, the controller 429 of FIG. 6 ) provides data forcontrolling beamforming. For instance, the controller can be formed on afirst semiconductor die that is coupled to a second semiconductor dieincluding the gain/phase control circuitry, and the controller canprovide data for controlling beamforming over a serial interfaceconnecting the dies. In certain implementations, software of thecontroller (for instance, software stored in a memory circuit of thecontroller 429 of FIG. 6 ) can control or determine settings forbeamforming.

Accordingly, the controller of the booster circuitry 43 is used tomanage beamforming in certain implementations.

In certain implementations, beamforming is used to angularly align beamstransmitted and received from a base station antenna of a signalboosting unit with respect to the mobile station antenna of cellularinfrastructure equipment or of another signal boosting unit. Forexample, beamforming can be used to correct for an installation error inpointing an active beamforming antenna array at another antenna.

Additionally or alternatively, beamforming can be used to regularlyrealign or calibrate a direction of beamforming to compensate forchanges in the relative position and/or orientation between the activebeamforming antenna array and another antenna. For instance, signalboosting units can be bumped or moved, which can lead to a change inantenna position and/or orientation over time.

Thus, beamforming can be used to align communications between a basestation antenna of a signal boosting unit and a mobile station antennaof cellular infrastructure equipment or of another signal boosting unit,thereby enhancing the strength of the wireless communication linktherebetween.

Such beamforming in the signal boosting unit can be separate orindependent of any beamforming in the cellular protocol, such asbeamforming information incorporated or built into 5G communications.For example, the signal boosting unit can be stationary absentoccasional changes to antenna orientation and/or position, and thus neednot track objects in real time. Accordingly, beamforming for a signalboosting unit need not decode the baseband signals to managebeamforming, but rather can provide beamforming that is additional to orsupplements any underlying beamforming in the communication protocol. Inanother embodiment, a signal is processed in a 5G NR beamformingprotocol layer to do active beamforming. Accordingly, the teachingsherein area also application to signal boosters that manipulate thelower layer protocol in an uplink direction and/or a downlink direction.

One example algorithm for beamforming in a signal boosting unit will nowbe provided. Such an algorithm can be performed by a controller of thesignal boosting unit, such as by using a processor and memory of thecontroller 429 of FIG. 6 , in combination with an active beamformingantenna array, such as the active beamforming antenna array 710 of FIG.9 .

In a first step of the example beamforming algorithm, the directioncontrol for beamforming is set in a neutral setting (for instance,non-directional), and the received signal strength is characterizedusing one or more power detectors, which can be included in the activebeamforming antenna array and/or in booster circuitry. For instance, ahigh speed power detector can be used to measure signal strength eachtime a time interval completes (for instance, every 10 microseconds overseveral seconds). For TDD communications, such measurements can occurduring receive slots, with a flat portion of the measured data used toidentify a pattern of signal levels.

In a second step of the example beamforming algorithm, the phase andgain associated with each antenna element is controlled to focus thebeam to point in a particular direction within the angular range of theantenna array, and step one is performed to measure signal strength forthis beam direction. The second step is repeated for multiple beamdirections, thereby collecting signal strength data for multiple beamdirections, such as beam directions spanning the full angular range ofthe antenna array.

In one example, the second step is performed by measuring signalstrength when pointing the beam in an upper left portion of directionalcontrol allowed, and thereafter incrementally moving the beam directionright and measuring signal strength until the angular range of theantenna array can no longer be moved right and a horizontal slice of theangular range has been covered. A horizontal sweep can be repeated foreach desired vertical beam setting, thus sweeping a desired portion ofthe area covered by the antenna array.

In a third step of the example beamforming algorithm, the beamformingsetting with about the highest receive signal strength can be used. Suchsetting can be fixed or static until the next beam direction calibrationis performed (if any).

In certain implementations, a coarse search is first performed bymeasuring signal strength for each of multiple coarse beam directions inthe angular range of the antenna array. After the direction with aboutthe highest signal strength is identified, a fine sweep can be performedfor beam directions adjacent to or nearby the beam direction identifiedby the coarse sweep. Additionally, the direction with about the highestsignal strength from the fine sweep can be used to as the selectedbeamforming setting.

FIG. 10 is a schematic diagram of a signal boosting unit 810 incommunication with a control device 818 (corresponding to a mobile phoneor tablet, in this example) according to one embodiment. The signalboosting unit 810 corresponds to one embodiment of an auxiliary signalboosting unit. Although depicted in the context of an auxiliary signalboosting unit, a primary signal boosting unit can also be controlledwith a control device in a similar manner.

In the illustrated embodiment, the signal boosting unit 810 includes ahousing 814 in which a base station antenna and booster circuitry havebeen integrated therewith. The signal boosting unit 810 further includesa mobile station antenna 815 connected to the housing 814 using a cable816.

As shown in FIG. 10 , the housing 814 is positioned in a first room 820a of a building, while the mobile station antenna 815 is positioned in asecond room 820 b of the building. Additionally, the cable 816 isprovided through an interior wall 821 of the building separating thefirst room 820 a and the second room 820 b.

The booster circuitry of the housing 814 is in communication with thecontrol device 818 over a communication link 822, which can be wired orwireless. In certain implementations, the booster circuitry includes acontroller (for instance, the controller 429 of FIG. 6 ) and/or a remotemonitoring circuit (for instance, the remote monitoring circuit 428 ofFIG. 6 ) that includes a transceiver for communicating with the controldevice 818.

The control device 818 includes a processor and memory for executing asoftware program or application associated with the signal boosting unit810. As shown in FIG. 10 , the control device 818 includes a display 823that is rendering information outputted from the software application.The information includes a graphical rendering 824 of the room 820 b, agraphical rendering 825 of the location of the mobile station antenna815 within the room 820 b, and a graphical rendering 826 of a radiationpattern of the mobile station antenna 815 within the room 820 b.

With reference to FIGS. 7 and 10 , in certain implementations, the cable816 of the signal boosting unit 810 is pluggable to allow selection ofdifferent mobile station antennas with different radiation profiles.Additionally, the control device 818 graphically depicts radiationpatterns corresponding to a particular mobile station antenna, therebyaiding the user in selecting a mobile station antenna suitable fordeployment in the room 820 b.

In another embodiment, the mobile station antenna 815 is configurable,for instance, implemented as an active beamforming antenna array inwhich characteristics of the beam (such as direction and/or strength)can be controlled by choosing gain and phase settings of gain/phasecontrol circuits associated with antenna elements of the array. In suchan embodiment, the mobile device 818 can be used to controlcharacteristics of the beam to aid in providing a beam directionsuitable for the room 820 b. For instance, the user can use the softwareapplication to select a beamforming setting, with the graphicalrendering 826 on the display 823 corresponding to the radiation patternassociated with the beamforming setting.

Example of Loss and Isolation Calculations

This section provides one example of loss and isolation calculationspertaining to high frequency cellular networks and signal boosters.

Table 1 below provides calculations pertaining to isolation for ahorizontal arrangement of a base station antenna and a mobile stationantenna. The calculations are generated based on an isolation formulaLh=22+20*lg(d/λ)−(Gt+Gr)+(Dt+Dr).

TABLE 1 Frequency(MHz) 28000 2100 700 Wavelength(m) 0.011 0.143 0.429Gain1(dB) 10 7 4 Front-to-rear 17 12 6 ratio; 1(dB) Gain2(dB) 10 7 4Front-to-rear 17 12 6 ratio; 2(dB) Distance1Feet 64.94 38.44 22.90Distance2Feet 70.96 44.46 28.92 Distance3Feet 74.49 47.99 32.44Distance2M 81.42 54.92 39.38

Table 2 below provides calculations pertaining to isolation for avertical arrangement of a base station antenna and a mobile stationantenna. The calculations are generated based on an isolation formulaLv=28+40*lg(d/λ)−(Gt+Gr)+(Dt+Dr).

TABLE 2 Frequency(MHz) 28000 2100 700 Wavelength(m) 0.011 0.143 0.429Gain1(dB) 10 7 4 Front-to-rear 17 12 6 ratio; 1(dB) Gain2(dB) 10 7 4Front-to-rear 17 12 6 ratio; 2(dB) Distance1Feet 85.89 40.89 21.80Distance2Feet 97.93 52.93 33.85 Distance3Feet 104.97 59.97 40.89Distance2M 118.84 73.85 54.76

Table 3 below provides calculations pertaining to isolation at 45degrees in which horizontal and vertical displacements of a base stationantenna and a mobile station antenna are equal. The calculations aregenerated based on an isolation formula Ls=(Lv−Lh)(α/90)+Lh.

TABLE 3 Frequency(MHz) 28000 2100 700 Distance1Feet 75.415 39.667 22.353Distance2Feet 84.446 48.697 31.384 Distance3Feet 89.728 53.980 36.667Distance2M 100.132 64.384 47.070

Table 4 below provides calculations pertaining to free space propagationpath loss. The calculations are generated based on a path loss model 20Lgf+20 LgD−27.55 dB.

TABLE 4 Frequency(MHz) D(m) Constant(dB) Path Loss(dB) 28000 100 27.56101.4 2100 100 27.56 78.9 700 100 27.56 69.3

Table 5 below provides FCC test report reference values of antenna gainand EIRP for different entities.

TABLE 5 Antenna Single Antenna Entity Gain(dBi) EIRP (dBm) Samsung 25 48Ericsson 24 46 Nokia 29 57 Samsung CPE 19 35~39

Table 6 below provides calculations pertaining to a Hata modelLb=69.55+26.16 lgf−13.821 ghb−α(hm)+(44.9−6.55 lgh)lgd. For example, Lbcorresponds to median smooth terrain radio wave propagation loss inurban areas, measured in decibels (dB). Additionally, hb corresponds tobase station antenna effective height (measured in meters), while hmcorresponds to mobile station effective antenna height (measured inmeters). Furthermore, d corresponds to the distance between mobilestation and base station (measured in kilometers), and α(hm) to mobilestation antenna height factor. At frequencies less than or equal to 300MHz, α(hm)=8.29[lg(1.54 hm)]2-1.1 dB, while at frequencies greater than300 MHz, α(hm)=3.2[lg(11.75 hm)]2-4.97 dB. With respect to a big cityoperating environment, hm=1.5 m, α(hm)=0, while for medium and smallcities hm=(1.56 lgf−0.8) and α(hm)=(1.1 lgf−0.7). Furthermore, forsuburbs Lbs=Lb (Urban area)−2[lg(f/28)]2−5.4.

TABLE 6 α (hm) Lb α (hm) med/small Lb med/small f (MHz) hb (m) hm (m) d(km) big city city big city city suburbs 28000 20.00 1.50 0.10 0.00 0.15131.53 131.38 108.13 28000 20.00 1.50 0.05 0.00 0.15 120.58 120.43 97.1828000 20.00 1.50 0.025 0.00 0.15 109.63 109.48 86.23 700 20.00 1.50 0.100.00 0.01 89.62 89.61 80.31

Table 7 below provides calculations pertaining to big city results for aHata model Lb=69.55+26.16 lgf−13.821 ghb−α(hm)+(44.9−6.55 lghb)lgd.

TABLE 7 donor BS d (m) receive ANT booster output retransmit EIRP BS tosignal gain gain power ANT EIRP f (GHz) (dBm) booster strength (dBi)(dB) (dBm) gain (dBi) (dBm) 28(E1) 48.00 50.00 −72.58 10.00 100.00 37.4210.00 47.42 28(E2) 48.00 100.00 −83.53 10.00 110.00 36.47 10.00 46.4728(E3) 48.00 25.00 −61.63 10.00 90.00 38.37 10.00 48.37

Table 8 below provides calculations relating to a number of small basestations deployed. The calculations are based on data from the precedingtables.

TABLE 8 # of small base coverage area # of small base stations per long(m) width (m) (square km) stations square km 500 500 0.25 100 400 500500 0.25 25 100 500 500 0.25 400 1600 500 500 0.25 100 400

Although one example of loss and isolation calculations have beenprovided in this section, calculation results can vary based on a widevariety of factors, such as models and/or parameters. Accordingly, otherresults are possible.

CONCLUSION

Unless the context clearly requires otherwise, throughout thedescription and the claims, the words “comprise,” “comprising,” and thelike are to be construed in an inclusive sense, as opposed to anexclusive or exhaustive sense; that is to say, in the sense of“including, but not limited to.” The word “coupled”, as generally usedherein, refers to two or more elements that may be either directlyconnected, or connected by way of one or more intermediate elements.Likewise, the word “connected”, as generally used herein, refers to twoor more elements that may be either directly connected, or connected byway of one or more intermediate elements. Additionally, the words“herein,” “above,” “below,” and words of similar import, when used inthis application, shall refer to this application as a whole and not toany particular portions of this application. Where the context permits,words in the above Detailed Description using the singular or pluralnumber may also include the plural or singular number respectively. Theword “or” in reference to a list of two or more items, that word coversall of the following interpretations of the word: any of the items inthe list, all of the items in the list, and any combination of the itemsin the list.

Moreover, conditional language used herein, such as, among others,“can,” “could,” “might,” “can,” “e.g.,” “for example,” “such as” and thelike, unless specifically stated otherwise, or otherwise understoodwithin the context as used, is generally intended to convey that certainembodiments include, while other embodiments do not include, certainfeatures, elements and/or states. Thus, such conditional language is notgenerally intended to imply that features, elements and/or states are inany way required for one or more embodiments or that one or moreembodiments necessarily include logic for deciding, with or withoutauthor input or prompting, whether these features, elements and/orstates are included or are to be performed in any particular embodiment.

The above detailed description of embodiments of the invention is notintended to be exhaustive or to limit the invention to the precise formdisclosed above. While specific embodiments of, and examples for, theinvention are described above for illustrative purposes, variousequivalent modifications are possible within the scope of the invention,as those skilled in the relevant art will recognize. For example, whileprocesses or blocks are presented in a given order, alternativeembodiments may perform routines having steps, or employ systems havingblocks, in a different order, and some processes or blocks may bedeleted, moved, added, subdivided, combined, and/or modified. Each ofthese processes or blocks may be implemented in a variety of differentways. Also, while processes or blocks are at times shown as beingperformed in series, these processes or blocks may instead be performedin parallel, or may be performed at different times.

The teachings of the invention provided herein can be applied to othersystems, not only the system described above. The elements and acts ofthe various embodiments described above can be combined to providefurther embodiments.

While certain embodiments of the inventions have been described, theseembodiments have been presented by way of example only, and are notintended to limit the scope of the disclosure. Indeed, the novel methodsand systems described herein may be embodied in a variety of otherforms; furthermore, various omissions, substitutions and changes in theform of the methods and systems described herein may be made withoutdeparting from the spirit of the disclosure. The accompanying claims andtheir equivalents are intended to cover such forms or modifications aswould fall within the scope and spirit of the disclosure.

What is claimed is:
 1. A signal booster system for a high frequencycellular network, the signal booster system comprising: a signalboosting unit comprising: a base station antenna configured to receive adownlink signal of a frequency band and to transmit an amplified uplinksignal of the frequency band, wherein the base station antenna isdirectional; booster circuitry configured to amplify an uplink signal ofthe frequency band to generate the amplified uplink signal, and toamplify the downlink signal to generate an amplified downlink signal ofthe frequency band, wherein the frequency band is a 5G frequency band; ahousing in which the base station antenna and the booster circuitry areintegrated; and a mobile station antenna configured to receive theuplink signal and to transmit the amplified downlink signal, wherein themobile station antenna is configured to connect to the housing by acable, wherein the booster circuitry includes a downlink amplificationcircuit configured to amplify the downlink signal, an uplinkamplification circuit configured to amplify the uplink signal, a firsttime division duplexing (TDD) switch configured to selectively connectthe base station antenna to an input of the downlink amplificationcircuit or to an output of the uplink amplification circuit, and asecond TDD switch configured to selectively connect the mobile stationantenna to an output of the downlink amplification circuit or to aninput of the uplink amplification circuit.
 2. The signal booster systemof claim 1, further comprising the cable.
 3. The signal booster systemof claim 2, wherein the cable has a length of 5 feet or less.
 4. Thesignal booster system of claim 2, wherein the cable is pluggable.
 5. Thesignal booster system of claim 4, further comprising a plurality ofmobile station antennas each having a different radiation pattern, themobile station antenna selected from the plurality of mobile stationantennas.
 6. The signal booster system of claim 1, wherein the basestation antenna comprises a parabolic antenna.
 7. The signal boostersystem of claim 1, wherein the mobile station antenna comprises a sectorantenna.
 8. The signal booster system of claim 1, wherein the boostercircuitry amplifies a full bandwidth of the 5G frequency band using asingle uplink amplification path and a single downlink amplificationpath.
 9. The signal booster system of claim 1, wherein the mobilestation antenna has a controllable radiation pattern.
 10. The signalbooster system of claim 1, further comprising a plurality of mobilestation antennas each having a different radiation pattern, the mobilestation antenna selected from the plurality of mobile station antennas.11. The signal booster system of claim 1, wherein the base stationantenna has a greater amount of directionality than the mobile stationantenna.
 12. The signal booster system of claim 1, wherein neither theuplink amplification circuit nor the downlink amplification circuitoperates with any frequency conversion.
 13. The signal booster system ofclaim 1, further comprising a primary signal boosting unit configured towirelessly receive the amplified uplink signal from the base stationantenna, and to wirelessly transmit the downlink signal to the basestation antenna.
 14. The signal booster system of claim 13, wherein theprimary signal boosting unit is fully integrated in a single housing.15. The signal booster system of claim 13, installed in a building,wherein the primary signal boosting unit wirelessly communicates withcellular infrastructure through a window of a first room of thebuilding.
 16. The signal booster system of claim 15, wherein the housingof the signal boosting unit is in the first room of the building, andthe mobile station antenna of the signal boosting unit is in a secondroom of the building.
 17. The signal booster system of claim 16, whereinthe cable of the signal boosting unit passes under a door between thefirst room and the second room.
 18. The signal booster system of claim16, wherein the cable of the signal boosting unit passes through a wallseparating the first room and the second room.
 19. The signal boostersystem of claim 1, wherein the signal boosting unit operates in a daisychain with at least one other signal boosting unit.
 20. The signalbooster system of claim 1, wherein the downlink amplification circuitcomprises a low noise amplifier, a first bandpass filter, a controllablegain amplifier, a second bandpass filter, and a power amplifier.